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Agotamiento del ozono: radiación ultravioleta y biología del fitoplancton en las aguas antárticas
R C Smith1, B B Prézelin, K S Baker
1Department of Geography, University of California, Santa Barbara 93106.
Science (New York, N.Y.)
|February 21, 1992
Resumen
El agotamiento del ozono estratosférico (O3) sobre la Antártida aumenta la radiación ultravioleta (UVB) dañina en el Océano Austral. Esta radiación UVB inhibe la fotosíntesis del fitoplancton, reduciendo la producción primaria en los ecosistemas marinos antárticos.
Área de la Ciencia:
- Biología Marina Biología Marina.
- Oceanografía La oceanografía es la oceanografía.
- Ciencias de la atmósfera Ciencias atmosféricas.
Sus antecedentes:
- La capa de ozono antártica se adelgaza significativamente durante la primavera, aumentando la radiación UVB en la superficie del océano.
- El fitoplancton en la zona de hielo marginal es vulnerable a los niveles elevados de UVB, lo que podría afectar a los ecosistemas marinos.
Objetivo del estudio:
- Para investigar los efectos del agotamiento del ozono estratosférico en la radiación UVB y la fotosíntesis del fitoplancton en el mar de Bellingshausen.
- Para cuantificar el impacto del aumento de UVB en la producción primaria en aguas antárticas.
Principales métodos:
- Un crucero de investigación de 6 semanas (Icecolors) en el mar de Bellingshausen durante la primavera austral de 1990.
- Medición de la superficie del mar y las proporciones dependientes de la profundidad de UVB a la irradiación total.
- Evaluación de la inhibición UVB de la fotosíntesis del fitoplancton.
Principales resultados:
- El adelgazamiento del ozono se correlacionó con un aumento de las relaciones UVB / irradiación total.
- El aumento de la radiación UVB inhibió significativamente la fotosíntesis del fitoplancton.
- Se estima una reducción del 6-12% en la producción primaria debido al agotamiento del ozono.
Conclusiones:
- El agotamiento del ozono altera la irradiación espectral subacuática, afectando los procesos fisiológicos del fitoplancton.
- La penetración de UVB debido al adelgazamiento del ozono representa una amenaza para la productividad primaria marina antártica.
- Los cambios en la dinámica del fitoplancton pueden tener efectos en cascada en los ecosistemas marinos antárticos.
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